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Title: EVALUATING NITROGEN AND PHOSPHORUS IMPACTS WITHIN WATERSHEDS OF THE GREAT LAKES BASIN
Creator: Hannah, Bailey A.
Date: 2022
Collection: Electronic Theses & Dissertations
Description: The Great Lakes and the streams draining to them provide an abundance of ecosystem services, including habitat, water resources, and recreational opportunities. The success and wellbeing of these water bodies are impacted by a variety of factors, including invasive species and septic systems. Along the shoreline of the Great Lakes, invasive species, such as Phragmites and Typha, are a major concern to the coastal wetlands. Within the inland river systems, near-shore septic systems can create...
Show moreThe Great Lakes and the streams draining to them provide an abundance of ecosystem services, including habitat, water resources, and recreational opportunities. The success and wellbeing of these water bodies are impacted by a variety of factors, including invasive species and septic systems. Along the shoreline of the Great Lakes, invasive species, such as Phragmites and Typha, are a major concern to the coastal wetlands. Within the inland river systems, near-shore septic systems can create elevated levels of nutrients that can have a collection of negative impacts. Both of these threats ultimately relate back to the presence and application of nutrients such as nitrogen and phosphorus. We first address the landscape conditions that allow for coastal wetland invasion. Using machine learning algorithms, we were able to quantify relationships between the presence of invasive species in coastland wetlands, and a variety of landscape scale variables – primarily the nutrient loads of nitrogen and phosphorus. We determined that high invasion is most strongly associated with nitrogen loading above 118 kg/ha/yr within the watersheds derived from the invaded wetlands. We then address how septic systems could be contributing to nutrient loads within the Manistee and Au Sable Rivers of Michigan. We modeled groundwater flow and the transport of nutrients to assess how competently septic systems are retaining nutrients. On average, septic systems allow 88% of introduced nitrogen, and 49% of phosphorus, to enter groundwater. These findings will inform watershed management and provide a better understanding of the effectiveness of septic systems.
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Title: DIRECTED IRIDIUM C(sp3)–H BORYLATION CATALYSIS WITH HIGH N-ADJACENT SELECTIVITY
Creator: Yadav, Anshu
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Modern approaches for the conversion of C–H bonds to C–B bonds involve transition metal catalysts that have various advantages over traditional methods by using cheap and abundant hydrocarbon starting materials, reducing toxic by-products and streamlining the synthesis of biologically important molecules. Metal-catalyzed C–H borylation reactions that produce organoboronic esters are mostly focused on the functionalization of sp2 C–H bonds of heteroarenes and aromatic hydrocarbons. However, in...
Show moreModern approaches for the conversion of C–H bonds to C–B bonds involve transition metal catalysts that have various advantages over traditional methods by using cheap and abundant hydrocarbon starting materials, reducing toxic by-products and streamlining the synthesis of biologically important molecules. Metal-catalyzed C–H borylation reactions that produce organoboronic esters are mostly focused on the functionalization of sp2 C–H bonds of heteroarenes and aromatic hydrocarbons. However, in this work the functionalization of sp3 C–H bonds is being explored. Borylation involving sp3 C–H bonds have been shown by Sawamura and co-workers with solid silica supported phosphine ligands offering a directing strategy where a metal center can accept donor directing groups. While this ligand generates highly active borylation catalysts, it requires a lot of steps in the synthesis of the ligand. In this work, easily synthesized homogeneous bidentate monoanionic ligands were tested for the borylation of sp3 C–H bonds. Herein is reported borylation of sp3 C–H bonds of N-methyl amide groups using [Ir(OMe)(cod)]2 as a precatalyst and B2pin2 as a commercially available boron source. Following the borylation of amide as a directing group, amidine molecules are being investigated.
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Title: BEHAVIOR OF ENTERIC PATHOGENS ON WHEAT GRAINS DURING TEMPERING AND EVALUATION OF INACTIVATION METHODS PRIOR TO MILLING
Creator: Lin, Yawei
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Outbreaks linked to Salmonella and Shiga toxin-producing E. coli (STEC) in wheat flour led to increased interest in characterizing the fate of these pathogens on wheat grains during processing and exploring potential inactivation methods. Despite the increase in water activity of wheat grains to ~0.85, the changes in the pathogen populations on inoculated soft wheat grains remained relatively stable during tempering. Using confocal microscopy, no significant redistribution of pathogen was...
Show moreOutbreaks linked to Salmonella and Shiga toxin-producing E. coli (STEC) in wheat flour led to increased interest in characterizing the fate of these pathogens on wheat grains during processing and exploring potential inactivation methods. Despite the increase in water activity of wheat grains to ~0.85, the changes in the pathogen populations on inoculated soft wheat grains remained relatively stable during tempering. Using confocal microscopy, no significant redistribution of pathogen was found based on the fluorescent intensity measurement. Chlorinated water had been used in the tempering solution in mills to control mold and yeast growth. When hard wheat grains were treated with 800ppm chlorinated water as a tempering over 18 hours, pathogen population changed from -2.35 to -0.30 log CFU/g, without negatively impacting the flour quality or functionality. Treating soft wheat at 75 ̊C using vacuum steam pasteurization, resulted in D75°C of Salmonella strains of 2.8 and 3.2 min of STEC ranges from 3.1 to 4.6 min, and of E. faecium was 3.3 min.
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Title: ADDRESSING WEED AND SOIL MANAGEMENT TRADE-OFFS IN VEGETABLES THROUGH INTEGRATED CULTURAL AND MECHANICAL STRATEGIES
Creator: Connors, Noelle Anne
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Mechanical cultivation is important for managing weeds in vegetables, but it can damage crops through uprooting or burial. We evaluated approaches to improve efficacy and selectivity of mechanical cultivation, and the impact of soil management practices on tool efficacy. Chapter 1 reports on experiments that test the effects of long-term reduced tillage and compost additions, as well as previous cultivation tool, on soil surface conditions, cultivation tool efficacy and yield in winter squash...
Show moreMechanical cultivation is important for managing weeds in vegetables, but it can damage crops through uprooting or burial. We evaluated approaches to improve efficacy and selectivity of mechanical cultivation, and the impact of soil management practices on tool efficacy. Chapter 1 reports on experiments that test the effects of long-term reduced tillage and compost additions, as well as previous cultivation tool, on soil surface conditions, cultivation tool efficacy and yield in winter squash. Compost addition had variable effects on soil conditions and efficacy between the two years, but increased squash mid-season biomass in both years and squash yield in one of two years. Surprisingly, reduced tillage had no detectable effect on soil surface conditions, cultivation efficacy, or yield. In one year, hilling at the first event improved finger-weeding efficacy at later cultivation events. Chapter 2 reports on field experiments evaluating the effects of carrot seed size and cultivation tool on cultivation efficacy and crop yield. We tested if larger seed sizes could increase carrot anchorage force and height at the time of cultivation and increase tolerance to cultivation. We found that 1) carrots from large seeds had higher anchorage force and height at time of cultivation, 2) tool effects varied by year and in one year large seeds increased cultivation tolerance, 3) yields were 20% higher from larger seeds. Chapter 3 presents a model to provide insight into the effects of crop and weed characteristics on selectivity of cultivation tools that uproot or bury weeds. The model was parameterized using anchorage force and height data from carrots and five weed species grown in a greenhouse, and predicts the effects of cultural practices influencing the relative size of carrots and weeds. It suggests that selective potential in carrots varies with crop growth stage and weed species, but is generally higher for tools that bury weeds than for those that uproot. The model demonstrates the impact of cultural practices including stale seedbedding and seed size selection on selective potential.
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Title: COVID-19 Among Community-Dwelling Residents of Saginaw County, MI : Race/Ethnicity and Urban/Rural Considerations
Creator: Dodak, Rachel A.
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Examining community trends related to demographic and socioeconomic risk factors associated with COVID-19 has been vital in informing public health strategies since the onset of the pandemic. This study is an exploratory epidemiological analysis of COVID-19 incidence and associated risk factors in individuals residing in Saginaw County, Michigan. This descriptive study used data on 2619 COVID-19 cases among Saginaw County, Michigan, residents confirmed between January and September of 2020 in...
Show moreExamining community trends related to demographic and socioeconomic risk factors associated with COVID-19 has been vital in informing public health strategies since the onset of the pandemic. This study is an exploratory epidemiological analysis of COVID-19 incidence and associated risk factors in individuals residing in Saginaw County, Michigan. This descriptive study used data on 2619 COVID-19 cases among Saginaw County, Michigan, residents confirmed between January and September of 2020 in the Michigan Disease Surveillance System. Two analyses were performed, one to examine COVID-19 outcomes (e.g., incidence, hospitalization, and mortality) between city and non-city residents by race/ethnicity, and the other to explore the association between household size and risk of COVID-19 infection at the census-tract level. Compared to those residing outside the city, city-dwelling Non-Hispanic White and Hispanic residents were more likely to have tested positive for COVID-19 (CIRR=1.28, 95% Wald CI: 1.08-1.51, p=0.004 and CIRR=1.87, 95% Wald CI: 1.49-2.35, p<0.0001, respectively) and were more likely to be hospitalized from COVID-19-related illness (CHRR=1.8, 95% Wald CI: 1.09-2.98, p=0.021 and CHRR=4.22, 95% Wald CI: 1.98-9.00, p=0.0002, respectively). Also, the COVID-19 incidence rate decreased, albeit non-significantly, with increasing household size per census tract (beta=-0.26, p=0.29). The urban-rural race/ethnicity COVID-19 disparities between Non-Hispanic White and Hispanic residents point to geographic and/or race/ethnic inequities in access to testing, treatment, and/or preventative measures for residents of Saginaw County, Michigan.
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Title: MEASURING COMMUNITY REVITALIZATION SUSTAINABILITY : EXPLORING SUSTAINABLE PRACTICES AND IMPACTS OF SUSTAINABLE BUILT ENVIRONMENT INITIATIVE (SBEI) PROJECTS IN MICHIGAN COMMUNITIES
Creator: Mouly, Armin Rahman
Date: 2022
Collection: Electronic Theses & Dissertations
Description: For years now, Michigan has been working toward revolutionizing the way its communities are designed, employing the ideas of sustainable development to mitigate the impact of urbanization on the community and environment and emphasizing promoting local resources. It is reported that several Michigan communities have been facing issues for the last few years (e.g., underutilized urban spaces, poor pedestrian movement facilities, lack of public places for city people, poor city appearance,...
Show moreFor years now, Michigan has been working toward revolutionizing the way its communities are designed, employing the ideas of sustainable development to mitigate the impact of urbanization on the community and environment and emphasizing promoting local resources. It is reported that several Michigan communities have been facing issues for the last few years (e.g., underutilized urban spaces, poor pedestrian movement facilities, lack of public places for city people, poor city appearance, safety, etc.). To address these issues and employ sustainable planning and design ideas for local affairs and opportunities, Michigan State University Extension (MSUE) and the School of Planning, Design, and Construction (SPDC) have jointly developed the Sustainable Built Environment Initiative (SBEI) to revitalize specific parts of cities and townships. In this regard, community meetings have been held since 2013 with a series of focus groups for each community with various stakeholders to obtain iterative input through a feedback process. The input and ideas obtained from these community meetings are used to generate actionable short, medium, and longer-term strategic plans and achieve specific sustainable goals.This study analyzes the SBEI projects in light of the future sustainable development of each community. The data for this study is collected from 14 previous SBEI projects that have taken place in 13 Michigan communities since 2014. Then interviews with diverse stakeholders, including local planners/city managers/associated entities, were conducted to understand further and analyze how these projects impact the future development approach over time. A holistic systems-based analysis of those areas from the perspective of individuals embedded in their social and institutional context is developed. In addition, three communities are selected to perform a sustainability assessment, for which a sustainability tool with indicators is used with metrics. The study attempts to evaluate whether the executed projects have met the expectations of the researchers and the community residents regarding sustainability and how the projects contributed towards the overall sustainability of the community. The findings are expected to play a significant role in future decision-making for communities dealing with sustainability challenges.
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Title: COMPARISON OF FIVE ACCELEROMETER METRICS FOR ASSESSING THE TEMPORAL PATTERNS OF CHILDREN'S FREE-PLAY PHYSICAL ACTIVITY
Creator: McKee, Katherine Louise
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Accelerometers are frequently used to measure physical activity (PA) in children, which is important for overall health and development. Lack of uniformity in data processing methods, such as the metric used to summarize accelerometer data, limits comparability between studies. The objective was to determine the convergent validity of five accelerometer metrics for characterizing the intensity and temporal patterns of first and second graders’ (n=88) recess PA. At a 5-s epoch level, Pearson’s...
Show moreAccelerometers are frequently used to measure physical activity (PA) in children, which is important for overall health and development. Lack of uniformity in data processing methods, such as the metric used to summarize accelerometer data, limits comparability between studies. The objective was to determine the convergent validity of five accelerometer metrics for characterizing the intensity and temporal patterns of first and second graders’ (n=88) recess PA. At a 5-s epoch level, Pearson’s correlations between various metrics ranged from 0.69 to 0.98. When each epoch was classified into one of four activity levels based on quartiles, agreement between metrics as indicated by weighted kappa ranged from 0.81 to 0.96. When collapsed to time spent in each activity level, metrics were most often statistically equivalent for estimating time spent in quartile 3 or 4. Children were ranked from least to most active, and agreement between metrics was strong with Spearman’s correlation coefficients of over r=0.86. Temporal patterns were characterized using five fragmentation indices calculated using each of the five metrics. Pearson’s correlations between metrics ranged from r=0.53 to 0.99, with the strongest associations for number of high activity bouts. Most fragmentation indices were not statistically equivalent between metrics. While metrics captured similar trends in activity intensity and temporal patterns, caution is warranted when making comparisons of point estimates derived from different metrics. However, all metrics were able to similarly capture higher intensity activity (i.e., quartile 3 or 4), the most common outcome of interest in intervention studies.
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Title: Gombe Group and Pliocene shield volcanism in Turkana : insights into the relationship between magmatism and strain
Creator: Cancel Vazquez, Sahira M.
Date: 2022
Collection: Electronic Theses & Dissertations
Description: The magma-rich East African Rift System (EARS) is a modern rift zone that provides an opportunity to constrain the existing relationship between magmatism and strain in continental rifts. Within the EARS, the broadly rifted Turkana Depression has been identified as an important locus of strain. This study focused on the magmatic events in the Turkana Depression that began in the Pliocene (ca. 4 Ma) as part of a pulse of basaltic activity known as the Stratoid Phase – the last pulse of...
Show moreThe magma-rich East African Rift System (EARS) is a modern rift zone that provides an opportunity to constrain the existing relationship between magmatism and strain in continental rifts. Within the EARS, the broadly rifted Turkana Depression has been identified as an important locus of strain. This study focused on the magmatic events in the Turkana Depression that began in the Pliocene (ca. 4 Ma) as part of a pulse of basaltic activity known as the Stratoid Phase – the last pulse of basaltic magmatism before strain was accommodated in the axial region of the Turkana Basin. This basaltic pulse began with the eruption of the widespread Gombe Stratoid Series and is followed by less voluminous basaltic activity in the form of shield volcanoes emplaced on top of the Gombe lava flows. We find that the Gombe Stratoid Series is representative of a high flux event with a complex magma plumbing system that was produced by large degrees of decompression melting of the upper mantle during a broad stretching event in Turkana. In contrast, the waning of magma flux resulted in the development of shield volcanoes subsequent to the eruption of the Gombe Stratoid Series. The timing of magmatic activity of some of the shield volcanoes suggests that there was a migration of magmatism towards Lake Turkana. Unlike the Gombe Stratoid Series lavas, we find that shield-volcano lavas require a component derived from metasomatized enriched lithospheric mantle. The contribution of this enriched component is more pronounced towards the east, coincident with a younging of magmatism in this direction. We suggest that the presence of easily fusible material in the continental lithospheric mantle in the vicinity of the Lake Turkana Basin may result in the generation of localized lithospheric melt following the broad plate stretching event that yielded the Gombe Stratoid Series. Lithospheric melts will promote the focusing of formerly broadly distributed plate stretching into a more localized region where plate melting may have occurred. We suggest that melting of enriched lithospheric mantle may account for the modern localization of strain and migration of magmatism and rifting towards the currently active volcanic centers in Lake Turkana Basin.
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Title: DEVELOPING INTEGRATED STRATEGIES TO ADDRESS EMERGING WEED MANAGEMENT CHALLENGES IN CHRISTMAS TREE PRODUCTION
Creator: Gallina, Greta Coreen
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Weeds must be well managed during the establishment phase (1-3 years) of Christmas tree production as weed competition directly relates to the rate of Christmas tree growth during this time. The objectives were to evaluate the weed control efficacy of organic mulch and herbicide combinations and to determine their phytotoxic effects on four different species of Christmas trees during the establishment stage and also to determine alternative postemergence control options for clopyralid...
Show moreWeeds must be well managed during the establishment phase (1-3 years) of Christmas tree production as weed competition directly relates to the rate of Christmas tree growth during this time. The objectives were to evaluate the weed control efficacy of organic mulch and herbicide combinations and to determine their phytotoxic effects on four different species of Christmas trees during the establishment stage and also to determine alternative postemergence control options for clopyralid resistant common ragweed (Ambrosia artemisiifolia L.), which has recently been discovered in Michigan Christmas tree farms. A field and greenhouse experiment were conducted. Four species of Christmas trees in their establishment stage were used for the field experiment: Fraser fir [Abies fraseri (Pursh) Poir], blue spruce (Picea pungens Engelm.), white pine (Pinus strobus L.), and Scotch pine (Pinus sylvestris L.). Twelve weed control treatments were applied for the field and greenhouse experiment with four replications each in complete randomized block design. The treatments were cypress bark organic mulch and the herbicides clopyralid, oxyfluorfen, and glyphosate, which were either applied alone or in combinations with each other. It was found that herbicides in combination with mulch resulted in better longer lasting weed control, but treatments involving clopyralid + glyphosate, even if mulch was also included proved to be the most phytotoxic treatments to the Christmas trees. Growth indices would likely only be affected later in the tree’s life and foliar nitrogen percent levels were found not to be affected by the use of mulch or any of the treatment combinations. Overall, the best treatments for controlling clopyralid resistant common ragweed were mulch + clopyralid + glyphosate and mulch + clopyralid + oxyfluorfen.
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Title: COMPARISON BETWEEN TELEHEALTH SERVICES AND TRADITIONAL IN-PERSON SERVICES FOR OPIOID USE DISORDER TREATMENT DURING THE COVID-19 PANDEMIC
Creator: Chen, Jing
Date: 2022
Collection: Electronic Theses & Dissertations
Description: The COVID-19 pandemic has stimulated the rapid growth of telehealth services. With the worsening of opioid overdose death and limited accessibility of opioid use disorder (OUD) treatments, the utilization of telehealth services for OUD treatments during the pandemic may be invaluable. We examined the patterns of such utilization and its relationship with the in-person treatment from April 1, 2020 to March 31, 2021 in a large health plan in southeast Michigan. First, the patients’ socio...
Show moreThe COVID-19 pandemic has stimulated the rapid growth of telehealth services. With the worsening of opioid overdose death and limited accessibility of opioid use disorder (OUD) treatments, the utilization of telehealth services for OUD treatments during the pandemic may be invaluable. We examined the patterns of such utilization and its relationship with the in-person treatment from April 1, 2020 to March 31, 2021 in a large health plan in southeast Michigan. First, the patients’ socio-demographic and comorbidity characteristics were examined by the Pearson’s chi-squared test for categorical variables and t-test for continuous variables between telehealth users and non-users. Next, we investigated whether the telehealth services were associated with the utilization of different levels of OUD treatments/cares by logistic regressions, adjusted by patient characteristics. Finally, we used a hurdle model to explore the factors associated with telehealth service use and the frequency of using the telehealth services. We found that patients were statistically different in most of their socio-demographic and comorbidity characteristics between telehealth users and non-users. Adjusted by covariates, telehealth users were more likely to take outpatient treatment, domiciliary partial residential care, behavioral therapy, medication for OUD, and buprenorphine for OUD treatment/care, while inpatient detoxification, intensive outpatient treatment, partial hospitalization, methadone and naltrexone had no statistically significant relationship with telehealth service use. Older patients had fewer telehealth visits compared to younger users, and patients living in the largest metropolis or more disadvantaged areas were less likely to use telehealth services. Telehealth services will be unlikely to replace in-person services, but may be a valued complement to in-person treatments during the COVID-19 pandemic.
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Title: INVESTIGATION OF GENETIC RESPONSES TO BOVINE LEUKEMIA VIRUS INFECTION IN BEEF AND DAIRY CATTLE
Creator: LaHuis, Ciarra
Date: 2022
Collection: Electronic Theses & Dissertations
Description: The USDA estimated 78% of US beef operations and 89% of US dairy operations are seropositive for Bovine Leukemia Virus (BLV). Cattle infected with BLV may suffer reduced immune function and productivity. Animals with advanced BLV infections may develop lymphoma, leading to carcass condemnation at slaughter. Research has revealed growing evidence of host genetic markers associated with BLV infection. While research on BLV in beef cattle is limited, BLV research in dairy cattle is plentiful. In...
Show moreThe USDA estimated 78% of US beef operations and 89% of US dairy operations are seropositive for Bovine Leukemia Virus (BLV). Cattle infected with BLV may suffer reduced immune function and productivity. Animals with advanced BLV infections may develop lymphoma, leading to carcass condemnation at slaughter. Research has revealed growing evidence of host genetic markers associated with BLV infection. While research on BLV in beef cattle is limited, BLV research in dairy cattle is plentiful. In dairy cattle, evidence of an association between the Bovine Leukocyte Antigen (BoLA)-DRB3 gene locus and proviral load (PVL) has been reported. However, these associations have not been explored in beef cattle. Chapter 1 investigates associations between BoLA-DRB3 alleles and BLV PVL in upper Midwest beef cattle populations (n=157). Associations between BLV PVL and BoLA-DRB3 alleles was determined. Alleles DRB3*033:01 and DRB3*002:01 were found to be associated with lower PVL and DRB3*026:01 with higher PVL. Chapter 2 explores epigenetic relationships between dam and her calf. Epigenetics can be studied through microRNAs (miRNA), a small noncoding RNA species involved in post-transcriptional gene regulation. Variations in maternal environment have long been associated with fetal development and health. The study will measure differential expression of circulating miRNAs in calves born to BLV infected dams (n=24). The study found four miRNAs in 14-day old calves born to BLV infected dams. Literature indicates the miRNAs are associated with immunological response, skeletal muscle development, and cardiac development. The presented thesis provides some of the first insights of allelic and epigenetic regulations associated with BLV infections in cattle.
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Title: Thermal Inactivation of Bacterial Pathogens Under Widely Changing Moisture Conditions in Cooked Bacon and Dried Apple
Creator: Randriamiarintsoa, Narindra
Date: 2022
Collection: Electronic Theses & Dissertations
Description: The overall goal of this thesis was to evaluate phenomenological similarity in bacterial pathogen inactivation under different thermal treatments of two very different food products (cooked bacon and dried apples) with similarly wide changes in moisture during processing. As ready-to-eat (RTE) products, both must comply with specific food safety regulations, under the United States (US) Department of Agriculture – Food Safety Inspection Service and the Food Safety Modernization Act Preventive...
Show moreThe overall goal of this thesis was to evaluate phenomenological similarity in bacterial pathogen inactivation under different thermal treatments of two very different food products (cooked bacon and dried apples) with similarly wide changes in moisture during processing. As ready-to-eat (RTE) products, both must comply with specific food safety regulations, under the United States (US) Department of Agriculture – Food Safety Inspection Service and the Food Safety Modernization Act Preventive Controls for Human Foods Rule, respectively. Therefore, there is a need for pathogen inactivation data to validate commercial pathogen control processes for both products. Both conventional and microwave oven cooking of bacon to the required 40% cooking yield achieved >6.5 log reduction of Salmonella. However, when humidity was reduced (dew point ≤25°C), microwave cooking of bacon yielded <6.5 log reduction. When drying apples to a standard moisture content (<24% wet basis), lower Listeria monocytogenes inactivation (1.8 and 2.8 log CFU) was achieved when drying at 60°C, under the studied air velocities (0.7 and 2.1 m/s) (P < 0.05), compared to 80°C, at which Listeria decreased by 5 log reduction by the end of drying. Despite the use of different pathogens, similar inactivation response patterns were observed during both apple drying and bacon cooking, especially microwave cooked bacon under dry conditions, reflecting the simultaneous counter-effects of dynamically increasing product temperature and decreasing product moisture. Therefore, results from this study suggest that it is theoretically possible to develop one model form for bacterial inactivation in widely changing moisture products.
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Title: FACTORS INFLUENCING ACTIVITY PATTERNS IN THE KENNEL AND CHANGES IN BEHAVIOR POST-ADOPTION IN SHELTER DOGS
Creator: Ampaiwan, Nattawipa
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Little is known about normal activity patterns of dogs in the shelter setting, how activity patterns influence adoption, or how activity and behavior develop in the new home after adoption. Our first objective was to compare dogs’ daily activity levels in the first week at the shelter and determine if activity levels were influenced by dog-related factors or contributed to the length of stay in the shelter. Activity was monitored via an accelerometer (Actigraph). Seventy-six dogs were...
Show moreLittle is known about normal activity patterns of dogs in the shelter setting, how activity patterns influence adoption, or how activity and behavior develop in the new home after adoption. Our first objective was to compare dogs’ daily activity levels in the first week at the shelter and determine if activity levels were influenced by dog-related factors or contributed to the length of stay in the shelter. Activity was monitored via an accelerometer (Actigraph). Seventy-six dogs were enrolled at a local shelter and activity was monitored for 24 hours per day during the first week. Results revealed that dogs display consistent patterns in activity levels between the first and last day of enrollment (t(74) = 6.67, P = 4.04-9), and dogs that display higher levels of activity stay longer at the shelter as compared to those with low activity levels (t(63) = 2.13, P = 0.04). In addition, male dogs show higher activity levels compared to females (t(70) = 1.70, P = 0.09). Our second objective was to quantify the behavioral changes in newly adopted dogs during the first three months after adoption and to identify the factors that correlate with behavior changes. Among 58 adopters, there were 10 adopters who completed C-BARQ behavioral assessment surveys for all seven post-adoption timepoints between day 3 and week 12. Results revealed that five categories of behavior did not change over time, while nine others varied in their expression between three days and three months. Based on these results, it appears that dog’s activity levels in the shelter and dog’s behavior changes at home were found to be influenced by the dog’s age, sex, and the interactions between the new owners and dogs at home.
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Title: RAPTOR FORAGING ECOLOGY AND ECOSYSTEM SERVICES IN AGRICULTURAL LANDSCAPES
Creator: Utley, Olivia
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Increasing agricultural productivity while improving sustainability of agricultural landscapes are key challenges facing society. One strategy to help address these two needs is enhancing pest-regulating ecosystem services provided by organisms that reside in these landscapes. To do so, we must understand the foraging ecology of these organisms and corresponding links to ecosystem services provisioning. In some contexts, raptors provide substantial ecosystem services by reducing damage to...
Show moreIncreasing agricultural productivity while improving sustainability of agricultural landscapes are key challenges facing society. One strategy to help address these two needs is enhancing pest-regulating ecosystem services provided by organisms that reside in these landscapes. To do so, we must understand the foraging ecology of these organisms and corresponding links to ecosystem services provisioning. In some contexts, raptors provide substantial ecosystem services by reducing damage to crops through consumption and deterrence of pest species. In this review we identify measures of raptor foraging ecology that may act as ecosystem service proxies, examine predictors of these proxies (e.g., vegetation structure), and discuss how this information could be used to enhance pest regulation by raptors. Through a literature search, we identified raptors’ use of cultivated land cover (use), attack rate, and successful attack rate as ecosystem service proxies for which we could analyze the effects of various potential predictors. Our results showed that increased amount of cultivated land cover, shorter vegetation, and shorter distance to the nest or roost increase use by raptors. We also found that shorter/less dense vegetation increased attack rate, although we found no effect of any predictors on successful attack rate. We suggest that growers maintain shorter vegetation immediately adjacent to crops and natural cover within the greater landscape, such as forest. We recommend future research investigate 1) additional farm management characteristics that could influence use and attack rates, 2) the spatial scales at which land cover type influences raptor foraging ecology, and 3) additional measures of raptor foraging ecology and their impact on the strength of pest regulation services.
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Title: What’s Behind the Impact : A Case Study of a Chinese Photojournalist’s Environmental Reporting
Creator: Du, Weiting
Date: 2021
Collection: Electronic Theses & Dissertations
Description: This thesis examines three environmental stories written and photographed by Chinese photojournalist Chen Jie and employs a critical qualitative analysis to research them and present their impact, including government actions and public engagement. Eventually, this thesis explores why these stories received a different response. This thesis is vital for understanding how environmental journalism gained impact in China, which is an under-researched topic. It examines and displays the selected...
Show moreThis thesis examines three environmental stories written and photographed by Chinese photojournalist Chen Jie and employs a critical qualitative analysis to research them and present their impact, including government actions and public engagement. Eventually, this thesis explores why these stories received a different response. This thesis is vital for understanding how environmental journalism gained impact in China, which is an under-researched topic. It examines and displays the selected stories and their different impact based on public information and an interview with Chen Jie. A set of assumptions that describes the context of environmental reporting in China was organized to situate this thesis’s arguments. Results suggest that the impact of an environmental photo story published during 2014-2015 in China is mainly influenced by four factors, the story and its publisher, public engagement, government engagement, and timing; the importance of the four factors ascends by order of precedence.
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Title: Evaluating the Impact of Weed Competition and Water Stress on Corn Hybrids with Differing Drought Tolerance
Creator: Rumler, Allyson Maureen
Date: 2021
Collection: Electronic Theses & Dissertations
Description: Water stress and weed competition are critical stressors during corn (Zea mays L.) development. Genetic improvements in corn have resulted in hybrids with greater abiotic stress tolerance; however, drought remains problematic. Therefore, with the expected change in precipitation throughout the Great Lakes Region, field (2019-2020) and greenhouse studies (February-April 2020) were conducted in East Lansing, MI to: 1) evaluate weed competition and water stress impacts on drought tolerant (DT)...
Show moreWater stress and weed competition are critical stressors during corn (Zea mays L.) development. Genetic improvements in corn have resulted in hybrids with greater abiotic stress tolerance; however, drought remains problematic. Therefore, with the expected change in precipitation throughout the Great Lakes Region, field (2019-2020) and greenhouse studies (February-April 2020) were conducted in East Lansing, MI to: 1) evaluate weed competition and water stress impacts on drought tolerant (DT) corn hybrid performance and 2) assess water stress and weed competition impacts on weed community composition and corn hybrid performance. In the field study, weed densities were lower under reduced precipitation and the communities were more diverse. As weed density increased, there was no difference in the rate of yield loss between drought sensitive (DS) hybrid under ambient or reduced precipitation. In contrast, as weed density increased the rate of yield loss was 1.8 times greater for DT hybrid grown under ambient precipitation compared to DT hybrid grown under reduced precipitation. Furthermore, as weed density increased the rate of yield loss was 1.3 times greater for DS hybrid grown under ambient precipitation compared to DT hybrid grown under reduced precipitation. There was no difference in the rate of yield loss as weed competition increased between DT and DS hybrid grown under ambient precipitation and DT and DS hybrid grown under reduced precipitation. Results from the greenhouse study confirm field study results. Overall, results demonstrate that reduced precipitation and increasing weed pressure decreases corn yield and impacts weed species diversity and evenness. Ultimately, integrated weed management will need to adapt to these changes for continued success under future climate scenarios.
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Title: Need for Affiliation Under Threat in the Context of Horror Video Games
Creator: Kim, Joshua
Date: 2021
Collection: Electronic Theses & Dissertations
Description: Research suggests that people favor playing violent video games cooperatively with others. However, little is known about the reason behind people’s desire to play cooperatively. Previous research has demonstrated that perceived threat to the avatar can increase the need for affiliation (Velez et al., unpublished data). The current study replicates and extends previous research by using a horror game, Phasmophobia. 559 American adults above 18 who have previous experience with video games...
Show moreResearch suggests that people favor playing violent video games cooperatively with others. However, little is known about the reason behind people’s desire to play cooperatively. Previous research has demonstrated that perceived threat to the avatar can increase the need for affiliation (Velez et al., unpublished data). The current study replicates and extends previous research by using a horror game, Phasmophobia. 559 American adults above 18 who have previous experience with video games were assigned to watch one of the four video clips of horror game play, taking the role of an avatar. The current research tested the hypothesis that direct violence to the avatar will result in higher level of threat relative to the avatar being in a threatening situation. The results suggest that perceived threat to the avatar increased participants’ need for affiliation. Also, participants who experienced direct violence to the avatar reported more threat than those whose avatars were in a threatening situation. Additionally, participants who thought their avatar was playing in a group reported higher levels of needs for affiliation. Finally, higher levels of need for affiliation increased participants’ desire to play video games with others but it did not predict an increased desire to play alone.
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Title: AN EXPLORATORY STUDY OF CHINESE SOCIAL MEDIA RESPONSES TO TESLA’S SAFETY FAILURES : DO COMMUNICATION STRATEGIES LEAD TO REPUTATIONAL HARM?
Creator: Wang, Jiawei
Date: 2021
Collection: Electronic Theses & Dissertations
Description: Social media has brought new challenges to multinational enterprises. Local users canpraise a product and possibly increase brand reputation, they can ask questions aboutreliability, or they can criticize a company and potentially harm reputation. Cultural differences may impact expected responses from companies, especially if they are dealing with safety failures of their products. Globally operating companies have to be aware of local norms in facing a crisis, especially if they come from...
Show moreSocial media has brought new challenges to multinational enterprises. Local users canpraise a product and possibly increase brand reputation, they can ask questions aboutreliability, or they can criticize a company and potentially harm reputation. Cultural differences may impact expected responses from companies, especially if they are dealing with safety failures of their products. Globally operating companies have to be aware of local norms in facing a crisis, especially if they come from different cultural backgrounds. This research explores social media reactions to one international company, Tesla, and their response to newsreported about productfailures. Using content analysis and purposeful sampling from China’s Sina Blog (similar to Twitter), comments and responses were gathered on the topic of Tesla’s security crisis for one month. The results show that despite initial negativity in social media response, in the long run, strategies such as ignoring and refusing to apologize may help the company restore some of the lost reputation.
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Title: EXPLORING THE EFFECT OF RELATIVE TIMING OF TARGET AND BACKGROUND WORDS ON SPEECH UNDERSTANDING WITH AND WITHOUT A BACKGROUND RHYTHMIC CONTEXT
Creator: Smith, Toni Marie
Date: 2021
Collection: Electronic Theses & Dissertations
Description: Using the Coordinate Response Measure (CRM) paradigm, recognition of target speech in the presence of competing speech has been shown to depend upon both the rhythmic context of target and background speech and fundamental frequency differences between the target and background speakers (McAuley et al., 2021). In the present study, two experiments examined the effects of the relative timing of target and background key words and the presence or absence of a background rhythmic context on...
Show moreUsing the Coordinate Response Measure (CRM) paradigm, recognition of target speech in the presence of competing speech has been shown to depend upon both the rhythmic context of target and background speech and fundamental frequency differences between the target and background speakers (McAuley et al., 2021). In the present study, two experiments examined the effects of the relative timing of target and background key words and the presence or absence of a background rhythmic context on target key word recognition using the same male talker for both target and background sentences. Experiment 1 varied the onset asynchrony between target and background key words when background rhythmic context was removed (i.e., the background consisted only of the competing key words) and Experiment 2 manipulated the rhythm of background speech leading up to key words, but left the key words intact with an onset asynchrony of ±50ms. Experiment 1 revealed an asymmetric U-shaped performance curve where (1) target recognition improved with increasing deviation of background key words from the expected onset timing of target keywords, and (2) target key words were better recognized when they began prior to the onset of background key words, compared to when they began after. With the reintroduction of the background context in Experiment 2, performance was reduced to chance both when the background rhythm was intact and when it was altered to be rhythmically irregular, suggesting that listeners were unable to distinguish target and background sentences and could not develop expectations for target key word timing
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Title: DEVELOPMENT AND CHARACTERIZATION OF TRAYS MADE OF POLYLACTIC ACID/ORANGE PEEL COMPOSITE BY DIRECT BLENDING AND MASTERBATCH PROCESSES FOR FOOD PACKAGING APPLICATIONS
Creator: Sawant, Pramit Pravin
Date: 2021
Collection: Electronic Theses & Dissertations
Description: Oranges are a very high production crop that produce a significant amount of waste after juicing. Value can be added to this waste if it can be reused as filler to produce packaging. However, thermoformed trays, which are broadly used in food packaging, have not yet been produced using agricultural waste. The aim of the first part of the study was to develop and investigate the properties of trays containing orange peel powder (OPP) using industrial thermoforming processing. The processing...
Show moreOranges are a very high production crop that produce a significant amount of waste after juicing. Value can be added to this waste if it can be reused as filler to produce packaging. However, thermoformed trays, which are broadly used in food packaging, have not yet been produced using agricultural waste. The aim of the first part of the study was to develop and investigate the properties of trays containing orange peel powder (OPP) using industrial thermoforming processing. The processing conditions necessaries for PLA/OPP tray production were determined and under these conditions, up to 30 wt% OPP was successfully added to PLA for PLA/OPP tray production. Thus, the first part of the study shows that OPP up to 30 wt% can be used for commercial production of thermoformed trays, without compromising most of the properties compared to neat PLA trays, which would reduce agricultural and plastic waste. Masterbatch process (MB), which improves the performance and properties of the packaging materials, has not been evaluated yet on agricultural waste. The second part of the study was aimed at investigating the effect of masterbatch by developing and comparing (1) trays with increasing amount of OPP produced by MB and (2) trays with the same amount of OPP produced by MB and direct blending. Trays produced using MB had better distribution of OPP that improved processability, which allowed for 5% more OPP (35 wt%) to be used as plastic filler. Therefore, this study shows that the use of MB increased the amount of waste that can be added to the polymer matrix during tray production and improved the properties of the trays compared to direct blending.
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